The invention relates to a pipe connection having a cutting ring which embraces the wall of the pipe and which can be pressed into same with at least one cutting edge, the cutting ring comprising a metallic compound, in particular an alloy with the constituents CrNiMo.
Pipe connections of that kind permit pipes to be quickly assembled by a solder-less screw assembly which is sealingly connected to the pipe associated therewith, by virtue of the cutting ring. Further details in respect of such screw assemblies are to be found in DIN 2353 (June 1991). Such cutting ring screw assemblies can be used as a lightweight construction in particular in relation to conduits for compressed air in the low-pressure range (up to 100 bars) and as a heavy-weight construction for heavy engineering, above 250 bars.
The cutting rings are usually made from austenitic standard steel (for example X 10 CrNiMo 18 10 2, material No 1.4571). Such cutting rings are too soft to cut into another steel. As austenitic steel does not pass through any transformation, it cannot be hardened; it is only possible to effect surface hardening in which an additional substance--for example nitrogen and/or carbon--is incorporated in the surface region. Admittedly that operation results in a surface hardening effect and thus ensures cutting durability, but at the same time such measures result in a particularly disadvantageous fashion in limitations in terms of resistance to corrosion of the basic steel.
In consideration of that state of the art, the inventor set himself the aim of improving a pipe connection of the kind set forth in the opening part of this specification and increasing the notching capability of its cutting ring without a reduction in other features in respect of quality.